1. Field of the Invention
The present invention relates to a webbing take-up device in which a spool is rotated by an urging force of a spring such as a spiral spring so that a webbing belt can be taken up by the spool.
2. Related Art
A male screw formed on one surface of an abut plate is threadedly engaged with a threaded hole formed in another end in axial-direction of a torsion shaft constituting a webbing take-up device disclosed in Japanese Patent Application Laid-Open (JP-A) No. 2005-289320 (hereinafter, Patent Document 1). A fixation pole formed on another surface of the abut plate intrudes in a spring cover. In Patent Document 1, an inner-side end in spiral-direction of the spiral spring is engaged with the fixation pole, but generally, a member referred to as an adapter, with which the inner-side end in spiral-direction of the spiral spring is engaged, is rotatably supported inside the housing (referred to as a spring cover in Patent Document 1) in a rotational direction of the spool. A fitting shaft formed to project from the other surface of the abut plate is fitted into a fitting hole formed in the adapter. Thereby, the torsion shaft and the adapter are coupled to each other so as not to be capable of relative rotation.
Incidentally, an outer peripheral shape of the fitting shaft formed to project from the other surface of the abut plate is a non-circular shape such as a star-like shape or a polygonal shape. Thus, the fitting hole formed in the adapter correspondingly to the outer peripheral shape of the fitting shaft is also a non-circular shape. Therefore, under a state in which a phase of the fitting hole and a phase of the fitting shaft about a central axis line of the fitting shaft are shifted from each other, the fitting shaft cannot be inserted into the fitting hole. As a result, in order to fit-insert the fitting shaft into the fitting hole, it has been required such a troublesome operation as to align the phase of the fitting shaft and the phase of the fitting hole with each other.